Memory devices are common in electronic systems and computers to store data. These memory devices may be volatile memory, where the stored data is lost if the power source is disconnected or removed, or non-volatile, where the stored data is retained even during power interruption.
Many memory devices, such as magnetic memory and resistive memory elements, are very small. At least because of their small size, it is desirous to use these memory devices in many applications. One of the issues associated with both magnetic memory and resistive memory is the current switching ability for each of the multitude of memory cells and the distribution or density of the switching currents. One possible reason for inaccurate switching ability and distribution is non-uniform current density through the cell. Another possible problem is excessive heat generation caused by the use of currents with high amplitude to switch the data state of the memory cells. Among other things, this temperature increase reduces the stability of the memory elements. Another problem is a relatively long typical switching time (e.g., many nanoseconds) of such elements.
In some memory designs, a reduction in the size of the memory cell can reduce the needed switching current. However, there are major difficulties in implementing smaller sizes due to at least current limitations of fabrication methods like photolithographic patterning. It is desirable to reduce the switching current density in order to make a feasible memory device.